Soldiers from the Kenya Defense Forces carry a wounded colleague out of the Westgate Mall in Nairobi on Sunday. / Ben Curtis, AP

by USA TODAY

by USA TODAY

NAIROBI, Kenya (AP) - A senior security official in Kenya on Thursday disclosed for the first time what authorities believe are the names of two previously unidentified gunmen who carried out the attack on a Nairobi mall, killing at least 67 people.

The official, who insisted on anonymity because he is not authorized to give the information, told The Associated Press that the two are Ahmed Hassan Abubakar and Yahye Ahmed Osman. No details on the men were made available.

Authorities previously revealed the names of two other attackers as Abu Barat Al-Sudani, also known as Mohamed Hassan Dhuhulow, and Mohamed Abdinur Said. Dhuhulow had lived in Norway.

The al-Qaeda-linked Somali militant group al-Shabab claimed responsibility for the September mall attack, saying it was in revenge for Kenya's military deployment into Somalia. Police and soldiers responded to the attack, which devolved into a protracted multi-day siege that saw huge explosions and a large part of the mall collapse.

All four attackers were believed to be ethnic Somalis.

Dennis Brady, the FBI legal attache in Nairobi, said last month that the FBI, like Kenyan authorities, believes all four attackers died inside the mall.

"Our ERT (Evidence Response Team) made significant finds, and there is no evidence that any of the attackers escaped from the area where they made their last stand," Brady said, adding that a secure crime scene perimeter made an escape unlikely.

The four gunmen arrived in Kenya in June and were previously in Somalia, officials have said.

Despite press reports during the mall siege that the attackers had hostages and had prepositioned weapons or ammunition inside the mall, no evidence has emerged to back those claims.

Four ethnic Somali men have been charged in Kenyan court with assisting the attackers. Their trials are ongoing.

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